The present invention relates generally to printing presses and more specifically to web offset printing presses having separable blankets.
U.S. Pat. No. 4,240,346 describes for example a printing press with two blanket cylinders separable from each other to permit a blanket throw off. In such presses, the blankets are offset from a vertical from each other, and in order to pass the web through the blankets when the blankets are offset, lead rolls or air bars are necessary to properly guide the web through the blankets. These guides can mark the printed product and also alter registration of the web between two printing print units, causing deteriorated print quality.
U.S. Pat. No. 6,439,117, hereby incorporated by reference herein, discloses a printing press having a multi-plate plate cylinder which permits for independent removal of each printing plate while the other printing plates remain attached. The press also includes a tucker bar adjacent the lock-up bar, the tucker bar including at least a first segment for tucking and holding the first printing plate on the plate cylinder and a second segment for tucking and holding the second printing plate on the plate cylinder, the first segment being independently movable with respect to the second segment.
U.S. Pat. No. 6,595,135, hereby incorporated by reference herein, discloses a printing unit with a plate cylinder having an axially extending gap. A tucker bar has an operating position, the tucker bar in the operating position capable of tucking a tail end of a printing plate into the axially-extending gap. A tucker bar control device automatically moves the tucker bar away from the operating position to a non-operating position.
U.S. Pat. Nos. 6,216,592 and 6,019,039 describe printing units with throw-off mechanisms and are hereby incorporated by reference herein.